HIV/AIDS and OIDS 6-8 Flashcards
HIV Patho
MOA:infected, HIV RNA released into host –> our body cells make antibodies –> over time, HIV destroys and drops CD4 levels –> progress to AIDS
1. early: when virus replicate massively (viral load VERY HIGH)
- could have flu-like s/s
- destroys CD4
2. latent: continue to replicate low levels (still transmissable)
-may be asymptomatic
-CD4 continue to decrease
3. AIDS (late): most severely damaged immune system –> vulnerable to opportunistic infx and cancers
-CD4 levels dropped critically
role of CD4
-CD4 (T helper) sounds alarm to activate immune system when they detect intruders (leads to B cells producing antibodies)
-normal: 500-1,000
-AIDS: < 200
(the moment diagnosed with drop in CD4: immediately start treatment regardless in CD4 count or stage)
-Viral load: goal is to decrease it to undetectable numbers
(< 20-75 copies/mL)
transmission of HIV
-all bodily fluids (blood, secretions) (sexual, transfusion, IV, fetus)
-NOT transmitted by air/water, saliva/sweat/tears, pets, toilets
-questionable transmission if viral load undetectable for 6months or longer (undetectable = untransmittable)
-measure viral load q4-6months
treatment recommendations
-start treatment regardless CD4 count or phase
==>GOAL: increase CD4 count and decrease viral load
-CD4: within 500-1000
-viral load: less than 20-75
-to prevent resistant –> multi drug therapy
lab tests
-CD4: tell us degree of immunodeficiency, if txt working, when to initiate txt or change meds
-viral load: predict pt outcome
-HLA-B*5701 screening: prior to Abacavir (drug) –> if positive: DONT use drug bc risk hypersensitivity
-CCR5 tropism (entry inhibitors): only effective against CCR5 strains
-hepatitis screen
=baseline screens: CBC, CMP (renal, liver, BG, lipids)
fusion inhibitor (block step 2)
[know Enfuvirtide (Fuzeon)]
-MOA: block fusion of HIV to host cell surface
-only fusion inhibitor we have
-SQ only, twice daily
CCR5 Antagonist
Maraviroc (Selzentry)
-MOA: chemokine receptor 5 anatagonist (for specific CCR5-trophic strain, more difficult to treat)
-worry abt liver, heart (like MI)
reverse transcriptase inhibitors (block step 3)
[know Efavirenz (Sustiva)]
MOA: NRTI; reverse transcriptase inhibitor
Abacavir: NRTI, mainstay treatment (now 1st line as well)
-PO
-contrainidcated if + HLA-B*5701 (bc hypersensitivity rxn)
-lactic acidosis hepatomegaly with steatosis
-MI (no give in CVS history)
-stay away from alcohol
Efavirenz (Sustiva): ONLY NonNucleosideRTI recommended for 1st line HIV (starting point)
-PO (dont take with high fat meals bc decrease plasma levels)
-NO PREGNANT!!!!!!!!!
-increase AST/ALT: monitor LFT
-CNS: dizzy, insomnia, impaired LOC –> give bedtime, safety precautions
-decrease effect oral contraceptives!!!!!!!!
reverse transcriptase inhibitors (block step 3)
[know Zidovudine (AZT; Retrovir)]
-MOA: NucleosideRTI
-drug of choice for pregnancy
-penetrates CSF
ADVERSE
-hematologic toxicity
+hold if hgb below 5 or 25% drop from baseline
+hold if neutrophil below 750
-lactic acidosis: potentially fatal
-myopathy
-GI and CNS effects
CAUTION with
-other myelosuppresive drugs
-drugs toxic to circulating blood cells –> increase hematologic toxicity (ex: Ganciclovir)
integrase inhibitors: general
(block step 4)
-MOA: integrase is viral enzyme that integrates DNA into host’s DNA –> block integration
Raltegravir (first line in combo)
-no give with PPI
-worry abt really bad headaches, SJS, hepatic toxic, myopathy, rhabdomyolysis
Dolutegravir: less resistance
-no give multivitamins, minerals (Fe, Ca, Mg) at same time bc decrease levels of drug –> space out 2h
-elevated LFTs, hypergly, insomnia (take at bedtime?)
protease inhibitors: general
(block last step 7)
-MOA: protease is last step in cleaving the mature HIV –> inhibits it so HIV remains immature and noninfectious
Darunavir: one of most effective
-MUST take with food!!! (in acidic environment)
-monitor CMP (hyperglu, hyperlip, increase bleed, incr LFT, reduced bone density and mineral)
-DONT CO-ADMINSITER with PPI
-no CYP450 inhibitor: no grapefruit juice
-no CYP450 inducer: no benzo (Midazolam), st johns wort
-no garlic
pregnant transmission
-mother to child: vertical transmission
-greatly reduced risk by ART (minimizes maternal viral load)
-take meds during preg and childbirth –> then baby take meds 4-6wks after birth
-C section can reduce risk of transmission
-feed formula instead bc HIV can spread thru breast milk
-AVOID: Efavirenz, Deltegravir
-protease inhibitors: increase risk gestational diabetes
HIV in children
-in young children: accelerated HIV course (have s/s by 1st bday, death by 5 even with meds bc immature immune system)
-diagnose by viral load rather than antibody testing
Pre-exposure prophylaxis (PrEP) of HIV
-MUST be negative HIV and hep B before start
-must agree to q3months HIV testing
-1 combination pill: Truvada daily (is a nucleoside analog reverse transcriptase inhibitor) –> wont protect against transmission of drug resistance
-still use condoms
Post-exposure prophylaxis
-oPEP: occupational (ex: healthcare)
-nPEP: non-occupational (ex: sexual assault)
-ONLY for emergency (if frequent exposure: PrEP)
-start ASAP but must be within 72h
-3 ARV meds for 28 days
(typically 2 NRTI and 1 PI)
